WASHINGTON — A marathon Senate investigation into allegations of CIA torture during the Bush-era war on terror is veering toward partisan political territory and possibly the federal courts after unusually pointed accusations against the spy agency, including potential criminal wrongdoing.

As a result of Sen. Dianne Feinstein’s remarks Tuesday, yet another investigation may be in the offing to sort out what the CIA did — or didn’t do — to help or hamper Senate investigators.

Already, the episode has the markings of a classic Washington controversy as interpretations of facts diverge, some lawmakers choose sides, others suggest the new probe and the White House seeks a middle ground.